Luminescent properties dependence of water-soluble CdTe quantum dots on stabilizing agents and reaction time

Abstract

The influence of stabilizing agents and reaction time on the luminescent properties of water-soluble CdTe quantum dots (QDs) was discussed. The thioglycolic acid (TGA)-CdTe ODs were characterized by TEM, XRD and FTIR. It is found that larger-size QDs can be synthesized more easily when L-cysteine (Cys) or golutathione (GSH) is chosen as stabilizing agent and TGA is proper to prepare highly luminescent QDs because of the effect between Cd²⁺ and sulfhydryl group. Furthermore, the absorption wavelength, full width at half maximum (FWHM), stokes shift, photoluminescence (PL) quantum yield and PL stability of TGA-CdTe are strongly dependent on reaction time, in which the absorption wavelength changes against reaction time with an exponential function. The TGA-CdTe QDs prepared at 2 h possess more excellent luminescent properties.

Keywords

CdTe quantum dots / stabilizing agent / reaction time / luminescent property

References

[1] ChenL.-d., LiuJ., YuX.-f., HeM., PeiX.-f., TangZ.-y., WangQ.-q., PangD.-w., LiYan.. The biocompatibility of quantum dot probes used for the targeted imaging of hepatocellular carcinoma metastasis [J]. Biomaterials, 2008, 29(31): 4170-4176

[2] GaoX. H., CuiY. Y., LevensonR. M., ChungL. W. K., NieS. M.. In vivo cancer targeting and imaging with semiconductor quantum dots [J]. Nat Biotechnol, 2004, 22(8): 969-976

[3] CaiW. B., ShinD. W., ChenK., GheysensO., CaoQ. Z., WangS. X., GambhirS. S., ChenX. Y.. Peptide-labeled near-infrared quantum dots for imaging tumor vasculature in living subjects [J]. Nano Lett, 2006, 6(4): 669-676

[4] YuW. W., QuL. H., GuoW. Z., PengX. G.. Experimental determination of the extinction coefficient of CdTe, CdSe, and CdS nanocrystals [J]. Chem Mater, 2003, 15(14): 2854-2860

[5] LiuY. S., SunY. H., VernierP. T., LiangC. H., ChongS. Y. C., GundersenM. A.. pH-sensitive photoluminescence of CdSe/ZnSe/ZnS quantum dots in human ovarian cancer cells [J]. J Phys Chem C, 2007, 111(7): 2872-2878

[6] KapitonovA. M., StupakA. P., GaponenkoS. V., PetrovE. P., RogachA. L., EuchmülierA.. Luminescence properties of thiol-stabilized CdTe nanocrystals [J]. J Phys Chem B, 1999, 103(46): 10109-10113

[7] LiuY. F., ChenW., JolyA. G., WangY. Q., PopeC., ZhangY. B., BovinJ. O., SherwoodP.. Comparison of water-soluble CdTe nanoparticles synthesized in air and in nitrogen [J]. J Phys Chem B, 2006, 110(34): 16992-17000

[8] TalapinD. V., RogachA. L., ShevchenkoE. V., KornowskiA., HaaseM., WellerH.. Dynamic distribution of growth rates within the ensembles of colloidal II–VI and III–V semiconductor nanocrystals as a factor governing their photoluminescence efficiency [J]. J Am Chem Soc, 2002, 124(20): 5782-5790

[9] MattoussiH., MauroJ. M., GoldmanE. R., AndersonG. P., SundarV. C., MikulecF. V., BawendiM. G.. Self-assembly of CdSe-ZnS quantum dot bioconjugates using an engineered recombinant protein [J]. J Am Chem Soc, 2000, 122(49): 12142-12150

[10] GaponikN., TalapinD. V., RogachA. L., HoppeK., ShevchenkoE. V., KornowskiA., EychmüllerA., WellerH.. Thiol-capping of CdTe nanocrystals: An alternative to organometallic synthetic routes [J]. J Phys Chem B, 2002, 106(29): 7177-7185

[11] ZhangH., ZhouZ., YangBai.. The influence of carboxyl groups on the photoluminescence of mercaptocarboxylic acid-stabilized CdTe nanoparticles [J]. J Phys Chem B, 2003, 107(1): 8-13

[12] TalapinD. V., HauboldS., RogachA. L., KornowskiA., HaaseM., WellerH.. A novel organometallic synthesis of highly luminescent CdTe nanocrystals [J]. J Phys Chem B, 2001, 105(12): 2260-2263

[13] RogachA. L., KatsikasL., KornowskiA., SuD. S., EychmüllerA., WellerH.. Synthesis and characterization of thiol-stabilized CdTe nanocrystals [J]. Ber Bunsen-Ges Phys Chem, 1996, 100(11): 1772-1778

[14] YuW. W., WangY. A., PengX. G.. Formation and stability of size-, shape-, and structure-controlled CdTe nanocrystals: Ligand effects on monomers and nanocrystals [J]. Chem Mater, 2003, 15(22): 4300-4308

[15] GUO Jia, YANG Wu-li, WANG Chang-chun. Systematic study of the photoluminescence dependence of thiol-capped CdTe nanocrystals on the reaction conditions [J]. J Phys Chem B, 109(37): 17467–17473.

[16] MandalA., TamaiN.. Influence of acid on luminescence properties of thioglycolic acid-capped CdTe quantum dots [J]. J Phys Chem C, 2008, 112(22): 8244-8250

[17] WangQ., KuoY. C., WangY. W., ShingG., RuengruglikitC., HuangQ. R.. Luminescent properties of water-soluble denatured bovine serum albumin-coated CdTe quantum dots [J]. J Phys Chem B, 2006, 110(34): 16860-16866

[18] DengD.-w., QinY.-b., YangX., YuJ.-s., PanYi.. The selective synthesis of water-soluble highly luminescent CdTe nanoparticles and nanorods: The influence of the precursor Cd/Te molar ratio [J]. J Cryst Growth, 2006, 296(2): 141-149

[19] DagtepeP., ChikanV.. Effect of Cd/Te ratio on the formation of CdTe magic-sized quantum dots during aggregation [J]. J Phys Chem A, 2008, 112(39): 9304-9311

[20] HeY., LuH.-t., SaiL.-m., LaiW.-y., FanQ.-l., WangL.-h., HuangWei.. Microwave-assisted growth and characterization of water-dispersed CdTe/CdS core-shell nanocrystals with high photoluminescence [J]. J Phys Chem B, 2006, 110(27): 13370-13374

[21] WangF.-b., FanM.-y., LiuY.-n., WangJ.-x., ZengD.-m., HuangK.-long.. Fabrication of ferrocenyl glutathione modified electrode and its application for detection of cadmium ions [J]. Journal of Central South University of Technology, 2008, 15(1): 44-48

[22] PanD.-c., JiX.-l., AnL.-j., LuY.-feng.. Observation of nucleation and growth of CdS nanocrystals in a two-phase system [J]. Chem Mater, 2008, 20(11): 3560-3566

[23] GerhardsC., DrostC. S., SgobbaV., GuleiD. M.. Conjugating luminescent CdTe quantum dots with biomolecules [J]. J Phys Chem B, 2008, 112(46): 14482-14491

[24] BorchertH., TalapinD. V., GaponikN., McginleyC., AdamS., LoboA., MÖLLERT., WellerH.. Relations between the photoluminescence efficiency of CdTe nanocrystals and their surface properties revealed by synchrotron XPS [J]. J Phys Chem B, 2003, 107(36): 9662-9668

[25] AlivisatosA. P.. Semiconductor clusters, nanocrystals, and quantum dots [J]. Science, 1996, 271(5251): 933-937

[26] MurrayC. B., BawendiM. G., KaganC. R.. Synthesis and characterization of monodisperse nanocrystals and close-packed nanocrystal assemblies [J]. Annu Rev Mater Sci, 2000, 30: 545-610

[27] TalapinD. V., RogachA. L., HaaseM., WellerH.. Evolution of an ensemble of nanoparticles in a colloidal solution: Theoretical study [J]. J Phys Chem B, 2001, 105(49): 12278-12285

[28] PengX. G., WickhamJ., AlivisatosA. P.. Kinetics of II–VI and III–V colloidal semiconductor nanocrystal growth: “Focusing” of size distributions [J]. J Am Chem Soc, 1998, 120(21): 5343-5344

[29] CondeJ. P., BhattacharjeeA. K., ChamarroM., LavallardP., PetrikovV. D., LipovskiiA. A.. Photoluminescence stokes shift and exciton fine structure in CdTe nanocrystals [J]. Phys Rev B, 2001, 64(11): 113303

[30] EfrosA. L., RosenM., KunoM., NirmalM., NorrisD. J., BawendiM.. Band-edge exciton in quantum dots of semiconductors with a degenerate valence band. Dark and bright exciton states [J], 1996, 54(7): 4843-4856

[31] MacholJ. L., WiseF. W., PatelR. C., TannerD. B.. Vibronic quantum beats in PbS microcrystallites [J]. Phys Rev B, 1993, 48(4): 2819-2822

[32] CaiW. B., HsuA. R., LiZ. B., ChenX. Y.. Are quantum dots ready for in vivo imaging in human subjects [J]. Nanoscale Res Lett, 2007, 2(6): 265-281